Device for regulating the length of the loops in straight bar knitting machines



1938- K. R. LIEBERKNECHT 2,140,240

DEVICE FOR REGULATING THE LENGTH OF THE LOOPS IN STRAIGHT BAR KNITTING MACHINES Filed Sept. 22, 1936 I 17 ut-a in: kau-Z Rickard Lteler /rwecht BY M W Patented Dec. 13, 1938 DEVICE FOR BEGULATING THE LENGTH OF THE LOOPS IN STRAIGHT BAR KNITTING MACHINES Karl Richard Licberknccht, oberlungwitz, Germill,

Application September 22. 1936, Serial No. 102,030

Germany September 25, 1935 6 Claims.

The present invention relates to the device which is used in straight bar knitting machines for regulating the length of the loops. The ob- .ject of'the invention is to provide a device of this kind which renders it possible to regulate the length of the loops automatically with simple means. 7

,As is known, the device for regulating the length of loops comprises a rotatable control shaft-which is connected with the needle bar, a control eccentric located on the eccentric shaft, a roller lever loosely arranged on the control shaft and an adjusting lever fixed to the said shaft. The roller in the roller lever contacts with the eccentric. The adjusting lever carries a set-screw, which presses against the loose roller lever. By rotating the set screw, therefore, the position of the coritrolshaft relative to the roller lever and the horizontal position of the frame needles relative to the sinkers can be altered. Herebyalso the depth of the sinking and the length of the loops are altered.

It is already known to automatically adjust the set-screw, which is arranged in the lever fixed to the control shaft, by means of a device which is actuated by a counter. a

The periphery of the control eccentric used is substantially circular for the part of it which corresponds with the sinking of the loops. The circular part of the periphery passes over into a projection, which is so formed, that during the subsequent working stages the proper division pressure, a correct shding off of the loops fromthe sinker beaks, et cetera, is secured.

Also by means of the known device it is possible to alter the length of the loops in the desired manner, but'the horizontal movements of the frame needle bar which must take place after the sinking of the loops are not controlled in the correct manner, because these movements aredependent on the length of loops itself. Therefore, if there is a great difference between the length of loops set and the length for which the eccentric is adjusted, the loops are not'formed in the proper manner and the quality of the goods is reduced. I

Due to the drawbacks which have been experienced at the said automatically operating device at the forming of the loops, this device has been replaced by a special control device for each commercial length of loops, which is equipped with an eccentric adapted to alter the length of loops. This control device has'however not only the drawback that it must be adjusted manually, but it is also very expensive and renders the handling of the machine difficult.

In order to obtain an automatical adjustment of the length of loops, without meeting the drawbacks of the known devise described above, according to the invention a plurality of control cccentrics is used, the forms of which are suited to the various lengths of loops. The roller levers carrying these eccentrics are adjusted simultaneously by means of .a set-screw and a control mechanism, and the rollers are displaceably arranged in such a manner, that at anytime only the desired eccentric acts upon the control shaft.

All the roller levers which are loosely arranged on the control shaft are suitably rigidly connected with each other, or a single rollerlever is used, in which all rollers are displaceably arranged.

In order to further simplify the machine, and in spite of this, secure loops of the desired form and size, according to the invention the'device is not equipped with an eccentric for each length of loops, but the entire field between the maximum and minimum lengths of loops is divided in separate individual sub-fields bordering upon one another, and for each of thesesub-fields an cecentric is provided. The number of eccentrics is so chosen,'that within each sub-field a proper working out of the loops is secured. a

An embodiment of the invention is illustrated by way of example in the accompanying drawing.

Fig. 1 shows the control device in elevation.

Fig. 2 shows the same device partly in side view and partly in section.

I denotes the control shaft, which in a manner known per se is operatively connected with the needle bar. in the drawing.

The eccentric shaft 9 carries two eccentrics I and 8. The entire field to be controlled between the maximum and minimum lengths of loops is thus in this embodiment of the invention divided or distributed on two eccentrics. Obviously also any other number of eccentrics maybe used.

The circular part of the eccentric corresponds with the depth of the sinking of the loops and the projecting part controls the'horizontal movements of the frame needles after the sinking of the loops has taken place. The form of this last mentioned part changes in dependency on the length of loops. The eccentric I behind the part located at the greatest distance from the centre has for instance a deeper groove than the eccentric 8.

The movements of the eccentrics 1 and 8 are This connection is not showntransmitted to the control shaft I by means of the roller levers 3, which are loosely arranged on the shaft I. In the embodiment shown, the rollers 5 and 6 cooperating with the eccentrics l and 8 are both carried by'the lever 3, which for this purpose is equipped with brackets 3a. The brackets serve as bearings for a shaft 4 on which the rollers 5 and 8 are seated. The roller 5 is rigidly fixed between the brackets 3a, whilst the roller 6 is slidably arranged on the shaft 4. The roller 8 is moved along this shaft by means of a fork 24, which projects into a slot 25 in the boss of the roller 6. The fork 24 is carried by a rod 22 which is coupled to the draw rod 23. Two

brackets 20 and 2| carried by the shaft 4 form bearings for the rod 22. A spring 26 forces the fork 24 to the right, whereby the roller 6 is held in engagement with the eccentric 8.

The movements of the loose roller lever 3 on the control shaft l are transmitted by means of the lever 2, which is rigidly fixed to the shaft I. 'I'hislever 2 carries a set-screw III which engages an adjustable stop on the lever 3. This stop is formed by a lever arm l2, which with one end is pivotally connected to the lever 3 and the other end of which carries a set-screw I3, which engages the lever 3. By rotating the screw l3, the position of the stop is altered. By means of this stop the fine adjustments of the control shaft are performed.

The set-screw or adjusting screw I is connected with a lever ll, which is moved together with the screw. I3 by means of a system of levers l5, l5, IT. The lever i6 is a double lever, which loops.

is pivotally arranged on a bracket 21, that is adjustably fixed to the control shaft by means of a screw. The movements of the lever I! are controlled from a counting device. After each movement of the levers l5, I6, I! the same are forced back into their original position by a spring l8. A spring I! strives to keep the levers 2 and 3 together.

In a suitable place on the lever or the roller lever loosely seated on the control shaft, besides the automatically operating adjusting device a. manually operated adjusting device may be arranged. In such case the lever corresponding with the lever I4 is formed as a hand lever. In order to facilitate the understanding of the draw ing this manually operated device is not shown.

When a stocking is knitted, the described de- ,vice operates for instance in the following manner:

During the forming of the top, the loop control is performed by the fixed roller 5 in cooperation with the appertaining eccentric.

When passing over to the leg, which usually 1 has finer loops than. the top, the formation of the loops is controlled by the system of control levers, which alters the angle between. the roller lever and the control lever rigidly fixed to the shaft in correspondence with the new size of the Since the difference between the sizes of the loops is not very great, it is not necessary to alter the division or distribution of the loops.

Since the eccentric with the deeper curved path is to be used for the control within the field of the small loops, the displac'eable roller rolling on the other eccentric must be kept away from its path on the eccentric as long as the device works in the field of the small loops.

When the-leg has been formed and the knitting of the heel commences,.the angle between the roller lever and the control lever is again altered in correspondence with the size of theloops.

from that of the first eccentric, that a correct distribution takes place within the field of the longer loops.

During this period; the first roller remains in position above its eccentric, without influencing the working-of the second roller, because the said parts of the second eccentric, on which the second roller operates, due to the larger loops, must be higher than the corresponding parts of. the first eccentric.

After the heel has been made, the knitting of the foot begins. All parts are now brought back into the positions which they took up during the knitting of the leg. The fixed roll thus again cooperates with its eccentric, whilstthe displaceable roller rolling on the second eccentric again is moved away from the same.

When the reinforced toe is knitted, which frequently is still more reinforced than the heel,

the second, displaceable roller again rolls on its path on the appertaining eccentric. Simultaneously the angle between the roller lever and the control lever rigidly fixed to the control lever isby means of the described system of levers readjusted for the new size of loops in the toe.

In the described embodiment thus loops of four different sizes are formed by alteration of the said angle, and for each two sizes, which do not differ widely from one another, only a single eccentric is provided, which allows the looping within this field.

L If regulations of loops 'within a wider range centrics, said roller levers being rotatably mounted on the control shaft, levers rigidly fixed to the control shaft, and a single adjusting screw for adjusting the roller levers by means of the fixed levers whereby the rollers cooperating with the eccentrics are so displaceably arranged that only one eccentric will influence the control shaft.

2. A device for regulating the length of. loops in straight bar knitting machines, comprising a rotatable control shaft connected with a needle bar, at least two eccentrics, a rollr for each eccentric, at least two roller levers rigidly connected with one another and cooperating with the eccentrics, s'aid roller levers being rotatably mounted on the control shaft, levers rigidly fixed to the control shaft, and means for adjusting the roller levers by means of the levers whereby the rollers cooperating with the eccentrics are so displaceably arranged thatonly one eccentric will influence the, control shaft.

3. A device for regulating the length of loops in straight bar knitting machines, comprising a rotatable control shaft connected with a needle bar, an eccentric shaft, atleast two eccentrics on the eccentric shaft, a roller for each eccentric, at least two roller levers rigidly connected with one another and cooperating with the eccentrics, said roller levers being rotatably mounted on the control shaft, and means for adjusting the roller levers whereby the rollers contact with the eccentrics and are so displaceably arranged that only one eccentric will influence the control shaft.

4. A device for regulating the length of loops in straight bar knitting machines, comprising a rotatable control shaft connected with the needle bar, an eccentric shaft, at least two differently shaped control eccentrics carried by the eccentric shaft, a roller for each eccentric, at

least two roller levers rigidly connected with one another and loosely arranged on the control correctly worked out.

shaft, levers rigidly fixed onthe control shaft for altering the position of the roller levers relative to the control shaft, and an adjusting screw for simultaneously adjusting the roller levers, the rollers cooperating with the eccentrics and being so displaceably arranged that always only one eccentric influences the control shaft. v Y

5. A device according to'claim 4, in which a stop is provided for the adjusting screw arranged on a; roller lever.

6. A device according to claim-4, in which the individual control eccentrics are so formed and stepped oif relative to one another, that each eccentric'can be used for a certain range of a continuous series of loop lengths and the individual eccentrics complete each other in such a manner, that all commercial loop lengths can be KARL RICHARD LIEBERKNECHT. 

